Kleven Verft’s Ulsteinvik shipyard delivered the 5,000 dwt PSV Juanita this month to shipowner J.J. Ugland, with a very unique feature.
This ship was designed by Salt Ship Design in Norway and is powered by a pair of in-line contra-rotating propellers which are controlled independently by two highly efficient permanent magnet motors. This propulsion system was designed as a joint effort between Salt Ship Design and Scana Propulsion.
Salt Ship Design notes, “Contra rotating propellers are in their nature more efficient than similar single propellers. Motors directly connected to the propellers gives fewer components, and improved energy conversion make the solution more efficient and safer compared to alternative solutions.”
The permanent magnet motors feature an integrated electrical motor and gearbox which Scana says, “eliminates mechanical efficiency losses in the gearbox while simultaneously increasing the efficiency of the electrical motor.”
Salt anticipates a 25 percent savings on fuel costs with this propulsion system as compared to conventional designs.
The ship is also powered by a pair of thrusters located in the bow and stern.
The U.S. Navy is also experimenting with permanent magnet motors on the recently christened USS Zumwalt (DDG 1000).
Watch the launching of the Juanita last September: